Colorectal cancer (CRC) screening is increasingly popular and is being more widely implemented. Colonoscopy is used not only in screening, but it may be recommended by colonoscopists for surveillance following polypectomy, because persons with polyps are thought to have increased future risk of CRC. Because about 30 to 50% of the US population has colon polyps, the number of persons enrolled in surveillance is potentially very large. Policy-makers are concerned that colonoscopy resources are being stretched and may need to be redirected, in post-polypectomy surveillance, away from persons with lower CRC risk and toward persons with higher CRC risk. Professional guidelines recommend that certain subgroups of persons, those with hyperplasic polyps or one small adenoma, may have no increased subsequent risk of CRC and thus should not need intensive post-polypectomy colonoscopic follow-up. However, a recent survey, based on physicians' self-report, suggests those physicians' recommendations for surveillance may be substantially more aggressive than guidelines suggest for these subgroups. The main objective of this research is to document, in community practice, the recommendations made at a person's first colonoscopy, regarding post-polypectomy surveillance. We propose to produce a population-based description of colonoscopists' recommendations for colonoscopy utilization in an entire state, by gathering data from approximately 200 practices where colonoscopy is performed, in the state North Carolina. For each physician performing colonoscopy, we will assess medical records in their offices for patients having a first colonoscopy. We shall collect data about patient history, the reason for colonoscopy, characteristics of polyps found, and physicians' recommendations for follow-up (e.g., time interval until next colonoscopy). We will contrast documented recommendations with published guidelines for subgroups of persons with different degrees of CRC risk, based on polyp characteristics. The information obtained in this study will describe use of colonoscopy in a population and document the relationship between practice and guidelines. It may provide the basis to develop interventions to optimize the allocation of colonoscopy effort in programs of CRC screening and surveillance.